Herbert hamilton scott and george mcintosh scott



mamas. 21,1925.

UNITED -s'rarssrarsu'r orr cs.

-mnnnr namu'ron' sco'r'r Ann ononoa mern'rosn soon, or nonnon, NGLAND.

, PRODUCTION O11 SHOW CARDS, ADVERTISEMENTS, SIGNS, DECORATIONS, OR THEv LIKE DY STENCILING. 4 a

' Io sw g. Original m. 1,516,065, dated November 18, 1924, Serial a...627,932, filed March as, 192:.

Application for reissue filed March 12, 1925. Serial No. 15,122.

I To all whom it concern:

/ Be it known that. HERBERT HAMmroN Sco n: and Gnoncn MoIN'rosH Soo'rr,subjects of the King of Great Britain, residing at 45 5 Kingsway,London, W. C. 2, England, have invented certain new and useful Improve-'ments.Relating tothe Production of Show Cards, Advertisements, Signs,Decorations, or the like by' Stenciling, of which the fol- D lowing is aspecification.

This invention relates to the production of showcards, advertisements,s1gns,'decorations or other decorative articles by stenciling, the chiefobject being to enable vitreous enamel metal signs and t e like to bemanufactured commercially in large numbers in a re id, inexpensive'andsimple manner.

H therto the commercial production of vitreous. enamel metal signs,particularly signs with complicated or multi-colored designs orlettering thereon, has been limited owing to the many operations andgreat labor and expense involved in the method of production hithertoemployed. The

drawback and limitations to printing methods with the aid of alitho-stone or zinc plate,the aerographing method, and the brushing outmethod are well known in the trade.

9 According to the present invention vitre-' ous enamel metal slgns orother decorative articles are produced by preparing ,avitreous-enameling composition or aint of suitable consistency anddrying c aracteristics,

applying the composition to a vitreous surface to be decorated by meansof a screen or stencil of silk or other meshed material having permeableand impermeable portions, and finally heating the article so treated Ito a. temperature sufiicient to cause fusion ofthe vitreous composition;In the prepara- T tion of the palnt or composition finely-v oundquartz-like enamel v013..enamel frit is used as the holly orfbase whichis colored as re uired b ename ing oxi es of commerce and worked up to asuitable consistency to pass through the meshes of the stencil employed.The fineness of the; powdered :materials should be as great .asis'necessary to enable thecompo'sition to pass through the meshes j ofthe stencil and the materials should there fore'be capable in their dryunmixed state means of the powdered of passin through a. screen of slihtly finer mesh. e have found-that a neness '.0f powder corresponding totwo hundred meshes to the square inch gives satisfactory I results. Thestencil used with such powder would have aboutl30 to MO'meshes to thesquare inch, but the fineness of powder used depends to some extent onthe'amount of detail to be shown on the metal sign.

In working up the powdered quartz-like enamel or enamel frit and oxidemixture into a suitable pasty mass a liquid mustbe used that will notpermit of too rapid drying, and yet' can eventually be dried completelywithout causingjthe surface to be spoilt by bubbles or otherwise whenthe article is subjected to the enamel fusing temperature. We have foundthat liquid of an oily character should be used. For example we havefound thata mixture com posed of one part by'volume of turpentine,-

1 part by volume of beeswax, and 8 parts by volume of parafiin oil givesexcellent results. This oily mixture is taken and mixed withapproximately three-times its weightof the quartz-like enamel or enamelfrit and oxide mixture and the whole is ground in a so speakingvaries-from 4 to 20 per cent. The; pasty composition is effectively andsimpl'y'-" applied by pressing it through the meshes of the stencil bymeans of a squeegee. After stenciling the vitreous enamel metal sheetsas above described we may first heat them suflicientlyto dryout the oilymedium and then heatthem-ih a mufile furnace or otherwise to la.temperature sufiiciently hi h.-.to cause fusion of the vitreous enamelack ound with the vitreous composition applied through the stencil, forexample from say about 600 to 10009 C. xdependln upon the nature of thecomposition. We t ereb obtain-real vitreous enamel sheet metal avertising signs or the like. I In carrying out our process particularat-"- tention is directed to the coo erative eflect between the vitreouspaste wit oily medium U and the permeable mesh portion of the stencil.In being pressed through the mesh, the vitreous paste is divided up intonumerous small particles and so deposited on the enamel base, andremains thus divided to enable the volatile matter to readily pass off.Upon .being' subjected to heat, all the ingradients of the paste exceptthe vitreous portion, are readil driven off at a temperature belowthatof the fusion point of the vitreous matter. As a result, whensubjected to the fusing temperature, the vitreous articles of the pasteare fused into a continuous smooth layer on the enamel base,

and are not subjected to the action of volatile matter being driven off.1 Were the paste td be put on. through a cut stencil having ties and.Without any mesh,'it could not be evenly applied, and furthermore, uponbeing subjected to heat, the volatile matters in the paste could not beso readily driven off since the paste would not be in a'finely dividedstate due to passage through stencil meshes. As a result the finishedproduct would be rough and uneven, due both to the imperfect aplication, and to the driving ofi of volati e substances during thefusion of the vitreous material.

B passing the vitreous paste through a me st'encil',.the mesh of thestencil so modifies the condition of the paste as deposited on the basethat the stenciled plate can befired to produce a smooth, even, andhighly glazed product.-

' In producing man-y designs a .cut stencil having ties cannot beemployed, but it is necessary to use a mesh stencih lVith" a,

mesh stencil, however, dry vitreous material cannot be dusted throughthe mesh. There was a problem to be solved in getting the groundvitreousv enamel through a mesh stencil in a satisfactory manner forvdesign purposes. As ointed out, the vehicle or carrier with w ich thevitreous enamel is mixed had to be a substance which would enable thevitreous enamel to be readily passed through the mesh and not dry out'too rapidly or clog the mesh, because the mesh stencil for practicaloperation must be p to used a number of times withgut having to becleaned. We found that-oils would enable the vitreous enamel to bepassed through thehmesh-without clogging; but the presence of any loilorgrease in vitreous enamel has been regarded as fatal to the.

production of. a perfect vitreous enamel sur:

' ace,.becau se the products of combustion from such oil or greasepassing through the" enamel, when fused caused blisters or pitting, -somuch so fllat'in: vitreous enamel factories great. care has alwaysbeen-exermedium was mixedto a pasty consistency and (passed through themesh, the paste woul' be appliedto-the surface small separated particlesas stated, which will not run together, .thus enabling the volatilematter to pass off freelv without blistering the enameL.

We have thus provided a volatilizable pasty medium for the particles ofvitreous material and thus made possible the use of a mesh stencil withavitreous enamel. Further, the action of the mesh of the sten-' oil onthe vitreous paste results in depositing the paste on thebase in acondition suchthat heating of the product will drive off the mediumportion of the paste and leave only the vitreousparticles when thefusing temperature has been \reached. Thus the 'medium portion of thepaste permits use of a mesh stencil for vitreous enamel work, and theaction of the mesh on the paste permits firing of-the product so thatvery satisfactory results are attained, a

The manufacture of vitreous enamel signs i enamel surface and thelettering or designs I consisting of metal plates having a vitreous beapplied and quickly dried'ready for the application of the next color,the actual fus- 1 ing of the colors if they do not overlap being carriedout in a single final fusing operation. With some vitreous enamels if itwere attempted to fire the article toenamel fusing temperature, afterthe application of each color of a three of more color design, theenamel would be over firedjand deteriorated. Accordingto our process,the stencils last a. considerable time before becoming defectivethroughwear and no technical skill or special plant such as is requiredfor lithograph work is necessary in using the stencils.

Vitreous enamel-metal signs and they like manufactured in accordancewith our in'-' vention are as durable as ordinary enamel ware and willwithstand rough usage and weather changes fora great length of timewithout deterioration.

Whatweclaim-isa Y ,1. Method of producing designs upon a vitreoussurface which comprises taking a pasty vitrefiable enamel compositionconasubdivided formupon said surface unti 3 heated, placing a fine meshstencil onto the vitreous'surface and forcing said composition throughthe mesh portion of the stencil onto the vitreous surface, whereby thecomposition will be applied to the design portion of the surface insubdivided form and finally heating the article to an enamelfusingtemperature.

2. Method of producing designs upona vitreous surface which comprisesplacing a fine mesh stencil onto the vitreous surface and taking a pastycomposition containing a fipely'ground enamel frit and an oily carrierand forcing said composition through themesh portion of the stencil ontothe vitreous surface, whereby the composition" will be applied to thedesign portion 'of the surface in subdivided form, and finally heatingthe article to an enamel-fusing temperature. v

3. Method of producingmulti-colored vitreous enamel designs and otherdecoraponent color of the design, forcin tive articles which comprisessuccessively applying component parts of a design of different colors toa vitreous enamel surface by successively placing onto the vitreousenamel surface a mesh stencil for each comthrough the mesh portion ofeach stenci a pasty composition containing finely ground vitreous enamelfrit and an oily carrier and of desired color, and between successiveapplications of such composition to the surface,

drying the component of the design thus applied, at a temperatureinsufiicient to fuse the enamel of the composition, and finally heatingto .anenamelfusin temperature the article bearing the m ti-colored de- 1In testimony whereof we have signed 40 our names to th s specification.

* HERBERT HAMiLToN soo'rr.

GEORGE McINTOSH- SCOTT.

